There’s a lot of excitement of Apple fans with the announcement of Apple’s first LTE-connected Apple Watch. However, the next hot button issue surrounding the idea of carrying a second cellular-connected device is: what will the $10/month add-on get you?

At T-Mobile, you won’t get anything faster than 512Kbps speeds on the new Apple Watch, this is according to the Un-Carrier’s website.

In order to get a wearable connected with T-Mobile, you must use the carrier’s DIGITS service, which allows you to mirror a T-Mobile line to a second SIM, or you can use it to connect any cellular-smartwatch with your number. But any smartwatch (Including Samsung’s) is limited to 512 Kbps with DIGITS.

DIGITS costs $15 per month or $10 with Auto Pay. However, according to MacRumors you can get "High Speed Data with paired DIGITS" for $20 per month or $25 without Autopay.

This shouldn’t be an issue to do basic smartwatch tasks. Even streaming Apple music should be okay as streaming music is (theoretically) half the bandwidth at 256 Kbps. However, if you feel that these speeds aren’t enough, you can always pay more.

There’s no word yet on which other carriers might be following the same rule for smartwatch data.